Lifting devices for animals are generally known. In the most general sense, they often incorporate a winch having a cable attached thereto and some form of sling lifted by the winch to cradle the animal inside of the sling apparatus. While such lifting devices are generally described and known, there is a need for a very specific purpose lifting device, designed especially for sows to allow for foot inspection and treatment. Such a device presents unique problems. For example, an effective immobilizing sow chute must be ‘sow friendly’. That is to say, the chute must be easy to enter, easy to exit, and causes no harm or alarm to the sow when she is restrained. An effective chute must prevent the sow from fighting, squealing, and kicking while her feet are inspected and/or treated. And the unit must be stable and safe when in the raised position.
Another special problem with sows is they are very heavy and that the hoist must allow hoisting of the animal in a manner that does not risk injury either to the animal's legs, shoulders, hips, or cause other internal injuries. Furthermore, the chute must present the sow in a manner which is safe for persons to inspect/treat the sow's feet. One way of avoiding injuries to the animal is to provide adequate support through the use of a sling, while maintaining the animal in a standing position during lifting. But slings per se have disadvantages such as difficulty in securing all four animal legs into the sling, danger of injury for workers while adjusting feet of the animal into the sling, agitation of some animals while harnessing the sling, risk of strap/apron failure, and danger of tangling with other parts of the device. They also require several workers to successfully operate.
Finally, an effective device to immobilize sows for foot examination must be one which can be operated by a single operator, because many times no one else is around. My earlier referred to application related to slings. As stated in some instances, it is desirable to avoid slings altogether.
While I have used slings successfully in the past for raising animals for foot inspection, they have some disadvantages as earlier mentioned and are disliked by some users. It would therefore be desirable to provide a non-sling option.
Another problem to be overcome by a successful chute is that it must have both mobility and stability. That is to say the unit must be easily moveable from place to place and at the same time, with the considerable weight of a sow within it when it is in up position it must be extremely stable.
Another problem with prior art chute units that have tried to go 100% electrical power is that they fail to have a backup system operable when there is an electric failure. This may be essential to getting a raised animal down.
Yet an additional problem with chute units which raise sows is that in the event of an electrical failure, there must be a stop system which will allow the operator to make sure that the animal does not fall from the elevated position to a lower position.
Finally, a special need for such units is that they must operate to provide maximum animal comfort and safety and the least amount of animal stress.
It is a primary object of the above invention to provide an immobilizing sow chute which can be entered from either end, which avoids the use of a sling, and which provides comfort, stability, and safety.
Another object of this invention is to provide an immobilizing sow chute which fulfills all of the above needs earlier described and which allows efficient operation by a single operator.
A still further object of the present invention is to provide a unit which has safety brakes to prevent the fall of a raised chute in the event of an electrical failure or hoist cable failure.
An additional object of the present invention is to provide a sow chute not only capable of entry from either end but which has contoured sidewalls to help support the animal's body for soft and relaxed holding of the sow.
An additional object of the present invention is to provide a highly mobile unit and a padded center pipe which the animal straddles until comfortably lifted off the ground.
The method and means of accomplishing each of the above objectives as well as others will become apparent from the detailed description of the invention which follows.